I just started reading about the three Spheres of Angles. Give me some edumacation please.

Doesn't the triumphal Hymn go:

... Angels, Archangels, Thrones, Dominations, Principalities, Virtues, Powers. Cherubim and Seraphim six winged many eyed...

Why are the Ophanim, Leaders, Rulers, and Authorities left out?Does the Eastern Faith have a different view of the ranks of Angles then the Western?